Ball-bearing rectilinear guideway and translation device



BALL BEARING RECTILINEAR GUIDEWAY AND TRANSLATIQN DEVICE Filed Sept. 10..947

3 Sheets-Sheet 2 ARNOLD KQLKS F e'. 4. BY l w/KM ATTORN EY.

Feb. 6, 1951 o s 2,540,125

' BALL BEARING RECTILINEAR GUIDEWA Y AND TRANSLATION DEVICE Filed Sept.10, 1947 5 Sheets-Sheet 5 g F e. 5.

v INVENTOR.

ARNOLD KOLKS ATTORNEY lotherhlchanis rn entailing "the f i'ictionofsfdf' should. iareferablymove rectilinear'ly;

patented Feb. 6, 19 V 2-;5'40J2-5 BALL-BEARING RECTILINEAR GUIDEWAY mamm qla nwn.

A 'n0,1d a'.Kolks;- New York,; N....Y..-. ain ieeii asee smks 91. Seria-ha? 981 IGZGlaims: (olefin-45 1- This invention relate to a new'andimproved. ant-i-friction'fiiiewai anql we comloinatidn m n theirnbroved; gfnideway: -'ai'1d' for; tianslati ng" 'rotajtionafmot'nfents into gu'id''d reotil'inea'r More fiai'ticnlarly'it i'elatesto a gnidewayhavmg no slidingvor slipping ba i'r' igsi1i"fac'e's*biitembloying an assembly 'stei bang and stam ed e'ratingf-iietefiorationwith use. addition like mg suirac'es; signi caht' 'amdunts of 130?WBLStEd' infliction. Ifn th'oaseof pre'c'i vices one particular -'disadvantage is 'thalt adhesion between riib b'ing sui fao'es""'a"cuatesettings andresettins are'diffioi lt'. 'Beause' dp these drawbacks,and i'n particfilr b eC'aTfi'S'' if? has been prohibitively exbens'iiie'to manufacture reliableguideways meeting high pirformanc'e'i iqui'iement's. at low cost, it hasbeen customary in 'many' ofthe arts to:substitute rotating parts wherever possible for elements which otherwiseIt is an object of :the present invention todevise a. new and improved'guideway offeringaminimum. of.- frictio'nutma guided element, i e'I'maximum freedomjor it in the guided. direction; and a-minimum'oi; free.play for. that element in any digestion other. than theguided.direction.

:It-isanother; object oi; this invention to. devise an anti-frictionguideway whose pantsflniayw -emade. by sim le. manufacturing. pnocessesI rom inexpensive materials. or are. g n ra y. Nels n a on 1116.4?511and=drawri vai able rea xzmade at low. cost, and aresubsqalet anfl agiys jectto easy assembly ofunskilled labor; Eig..-5;is.ai,deviewgofia'simplified embodiment It is another object of thisinventionto. devise Qf1 theimzention shown in'Fig. 1 in which each n;entivfrition uideway which is free from the inthe cams seri s alsoas'apfessurpl'at f Che fri tional, slidin slippin and rubbing. bearing 60 Qfthecamsisnartlycutaway; s rfaces and. thus is. subject to minimumwe'ai';Fig. (iis'v a SGCfiOYIal'ViEW .ofthe device of Fig.

Itisa further object 05 thisiinvention tov devise. 51ta'kn alongftheline 5. 6: t'ds'hov'fon'sh'itable a. .nov;el ,cleyicelbycombiningguidewayimeans of pathway 'forthe carmgi oovef' A gho'ti'fhatge is shown superimposed, on this view to illustrate how the twocam balls remain equidistant from each other as the cam is rotated.

Fig. 7 shows a circular pathway for the cam groove that mayalternatively be used in the embodiment of Fig. and

Fig. 8 shows a spiral pathway for the cam groove that may alternativelybe used in the embodiment of Fig. 5.

Frame l of Fig. 1 consists of a sheet metal stamping having a base plateportion la and two upright sides, lb and lo, which are bent up at rightangles from the base portion from opposite edges thereof. Frame I may beconveniently and economically formed in a power press and either by theinitial pressing operation therein or by subsequent similar ones itsupright sides may be formed to provide rectilinear ball raceways, shaftball bearing annular raceways, and top-edge reinforcing lips all ofwhich are fully described below. Similarly the base portion may bepunched to provide holes suitably placed for mounting the frame inaccordance with any particular intended use for the device, for example,onaradio chassis.

As can be seen from Fig. 1a a shaft 2 is supported between upright sideslb and la by two sets of balls 3 seated in opposed annular raceways 4each of which may be formed by pressing out some of the material of oneof the upright sides (and punching a hole through the center thereof) toform a cuplike inner working surface of the same shape as the otusidecurved surface of a short truncated cone. Shaft 2 has a groove 5 ofapproximately semi-circular cross section turned into its outer surfaceat each of the points thereof where the shaft will be supported on oneof the sets of balls. In assembling shaft 2, sets of balls 3, the frameI the shaft is slid through ths punched out holes in the upright sidesuntil each of its grooves is near the upright side in which it is to besupported; with the shaft held in a vertical position one set of ballsis dropped between the outer surface of the shaft and the inner surfaceof the annular raceway whose cuplike surface is facing upward, the shaftis slid upward or downward if necessary until this set of balls fallsinto place in the shaft groove intended for them; while a slight forceis exerted along the shaft axis to kee this set of balls captive againstthe cuplike surface the frame is inverted so that the other cuplikeraceway faces upward; the upright sides are sprung slightly apart andwhile they are in this condition the other set of balls are dropped intoplace between the upturned free raceway and the free shaft groove in themanner described above; the up right sides are allowed to spring back tohold both sets of balls captive; tension element 6 (see Fig. 1) isslipped over the top edges of the upright sides to exert a predeterminedamount of pressure to keep the shaft in true alignment but not undersufficient pressure to bind it. The tension element in addition tomaintaining shaft alignment will prevent frame I from becomingaccidentally spread to such an extent that the balls can fall out andbecome lost. If desired the tension element may be formed so that adjustment of tension is possible. For example, this element may consistof rod with screw threads and an adjustment nut'provided at one end sothat the nut could be turned along the rod as desired to providecontrolled tension between the upright sides. However, where thethickness of the sheet metal used is kept within predetermined limitsand where the balls are of uniform 4 size the tension element may, asshown in the drawing, consist of a fiat strip of metal with its endsbent over at right angles to form retaining surfaces spaced from eachother by a predetermined fixed distance.

As will be fully described below tension element '6 may be held in itsposition across the top edges of frame I by screws which play a part inholding together other elements of this device.

Each of the upright sides lo and lb has two rectilinear' racewayspressed into its outer surface. The axes of the raceways on an uprightside are parallel to each other and perpendicular to base plate portionla and in each upright side one of the rectilinear raceways is locatedon each side of the hole therein through which shaft 2 passes.Preferably the raceways may have V- shaped cross sections with spreadbetween the arms forming the V.

For certain applications it may be advantageous to polish the flatconverging surfaces of the raceways or to harden them by tempering, heattreatment, or chromium plating. However, for many applications a highstandard of performance will be achieved without any processing afterthe pressing operation. Applicable smoothing and hardening of certainsheet metals in the area of a press can be achieved inexpensively in thepressing operation itself by using dies and pressure appropriate tocause an appreciable flowing and compressing of the metal in the press.As is seen in Fig. 1 a small portion of the material at the top of eachof the upright sides is bent over at right angles to form top-edgereinforcing lips Id, le for the upright sides. It will be apparent aftera full description of this invention that for applications whereunusually accurate performance is required the stiffening effect of thereinforcing lips will serve an obvious good purpose.

An elevator element 1 consists of two halves, a front half and a rearhalf. The two halves are joined by a pair of screws 8 which pass throughelongated holes 9 in the front half and engage threads l0 in the rearhalf. This arrangement not only simplifies assembling of the device butas will be described below it permits independent adjustment of thefront and rear guideways.

When the halves are joined together elevator element 7 comprises a topp.atform portion la (consisting of two halves which are fastenedtogether by screws 8) and two guided sides lb and 7a which are bentdownward at right angles from the platform portion from opposite edgesthereof. The platform portion as measured between the outside edges ofthe top ends of the guided sides is Wider than the correspondingdimension of base portion la by an amount approximately equal to twicethe thickness of the sheet material used in forming elevator element 1plus twice the thickness of the sheet material used in forming frame lplus twice the amount or space maintained between each of the guidedsides' and the upright side cooperating Wish it by polshed balls whichare placed between them in a manner to be disclosed below.

When the elevator element is so proportioned with respect to the frameit will fit over the frame; its guided sides will fit around the uprightsides of the frame; and the polished balls, whose installation will bedescribed below, will fit between them in opposed raceways underappropriate pressure so that the elevator element will be movablymounted on the frame on rolling supports. There is punched out of eachof the guided sides a centrally located opening exerr-mares Theree are itwos pressure -plates I 92 Each: 05 themxonsistsmf: a: sheetmetallstamping of about theisamer sizes-andrashape as an. upright sideand-iihas ah'olepunched through? it in:a position comecanzbeassembledsover 'theaframe-iwi-th :theshafth: spondingztoathe.locationrof. the annular raceway ends: protruding throughti: theses?openings .andzt will beFfree' to :move iupszand downa'withhut beingimpeded by; the. shaft endsaeven; though they? extend; through. theguided: sidesa's. 'I'his punched? inazanazuprig'ht isidee. This: holein: each plate I issldrgeenoughatorpermitizthe: plate to he as;

sembledcagainst a guided %side1- withaa: shaft end?protnudingathroughzthe;hole; without-minding in.

out openingis widerzthan .thGFShaft-diametelf' bllt ioeitsr.Twocrectilinearrracew y re:s m d n the narrower thantthe'distanoezbetween' the recti=+- linear. raeewaysza H1.thi upright sides;This leaves solid material ion ea'cha'ofizthe guided-tsides into-"whichthere are: pressedeparallel zraeeways spaced :from' eaohnother byrthesame .zdistanoe a that betweenrthe rectilinear raeeways on eae ofgthe,upright sides. ofr-frameizI These aacewa-ysr which also-arerzrectilinear.vare-zpressedszinto th inner surfaces =0fthe3g1lid6disidesfli; e:' .the.=sur

pressure platemarallel to each.otherzandeparallel toe-theruprightrredgesof {the-pressure plate. Ass: cairzbe fbESt'iSGBDIxffOHI' Figs.- 1 "and.1b va'number" ofi:polishedssteelzballs 201' similar 2170". the balls I2:1

\ 16% mentionedr'ab'ove are usedttoproducezrolling re1a.-

tivee-moti-onbetween; each. pressure; plate and theeguided: sidewith-which- ;it :.coopera;tes;: Unlike? the eballsrl 2 however theballs-:2 Q are. noteaptivee betweenrtwo opposed M-raceways: Each-ball26;;

faces r of I the relevator'. elements-which? face eae ,i.mgwhileeitrisncaptive-aorr onersid'e in:rails-racewayins;

other: In. additiont:toubeingrparalleli. toaeac other and.thesearacewayszarez perpendi'eular t 1 top;,=p1atform :pportion". HT.and; for. each guide 5'2 side, one of the racewaysoiseformedz in-:the ma'thattsurfaceoi' .a' pressure-plate :ifItUWhiOhriitSrs Vsraeeways .werepressed: is rheld: ;in -placexonz:'ts

other sideeby impinging upon theesurfaceruof a;

uidede. side opposite --to that ,into which its V-.-*-

terial-remaining on ea'chrsideiofif the centi al I S- D Theimfltalp ssdback'i openingr after it is punched: out;. These: race Ways: have: the:samercross-zsectional shape= s described. above forthosedir.the-'upright sides:

In adding a the elevator element: 1 t0 the sub tolform ma V-..-g1;ooye;on .the front-surface -of an guided side. forms. an inverted Vprotrusion on= backesurfaee and thisprotrusion has a. shoulder" uponwhich polishedsteel balls 28 may conassembly?comprisingfframe'z I,.sh'aft i' sets of-" aer bearrand alonezwhich therrwill beifree pair ofracewaysrathus alignediwit I i-"loosely fit m' ting -'retaine'r-holesi'I 3a": in: one of thetab's I 311 ofa spacencageilfi3(o1'1e:of which hadpreviously" been: slipped: over. each. orithe edges of each guidedside-with: one offits tabs against its to. roll;

Though. each individual. ballv 20.. thus; ridesev mainvertedjV-'protrusion insteadiofbetween tWQa wa11s1as in a V-shapedgroove,nevertheless .op.-.. posed different onesiofth'e balls 2|] bear. onshoule; derswhich face away from each other and; therefore,'good 'guidinaction results.

However, Fig; lcwillustrates an. alternatelarr rangementfor': theraceways by which the balls 20; as 'wellia's therballsr l2',..are.captivebetween... v raceways'impin'ging on them from two. opposite.sides: This arrangement has s an additional ';ad-"

side surfaceand the-ioth'er. againstits outsi'de Vantage thataTsetOfTdieSr Suitable for pi surface) the guidedisides 'are pressed'firmlytd ward each :other andiagainst the upright sidesstdhold the:steel 1 ballsscaptive abetween the aligned raceways; and screws: 8 areset -ir r place and raeeways into the uprightsides :and. the. guided"-sideimayalsob'e'usediforstamping; raceways into; the *pressureplate:Moreover, this arrangement? permits the use of a-larger "number of theballs tightened 'to maintainzthis pressure until 'a'--1ate1'"=* 5IFandthusprovid s'an increased o l rin Each :ofthe "halves of theelvator elment tin cludes a :lug I d'by.rwhielrielevator element maw bedriven upward or downwardiirrthe guidd area": Raceways; as "showniinTig:la are formed in'" pairs" ofv' grooves; each groove of each pair": beingparallel to'andadjacerrt to the other one so that "together-they have aW-shaped cross section;

direction; :Asz'ca'nsbetseenfrom Fig Leach-of the r ss d n-s de and d edp w cross 'section pm the oppositeside: Obviously; a-

w eross'sectionincludes two"V- cross-' sections and an inverted-"W-cross-section-- includes a V-cross sectiom Therefore; by reversingeaoh pressure or; a subsequent: pressings operation" so tha t it platein-ae b e" V Cd W comprises .-=an: extension I 5':- wh'ieh may be inanesame plane as topvplatform portion and which extends outward beyond: theplaneof- 'the guided' side and alugtpjortiom ifi'bent down at rightanglesfrom-'the 'endiofrexte'nsiom I S te provide a..surfaoe parallelto? thate of the guided side-*- in which thereisrformedazshorttransverse raee way I L The ero'ss'ssectionlofs this---r'aeewa5may" be similar to :thatof thezrectilinear raceways al surface faees therear surface of a guided side;

registered v groove'draceways will be afiorded" and held captiVer Wheremmaximum 1 manufacturingeconomy desired 'the pressure platermaybemade-flat; i5 e-.-'-

without. any pressed' im racewaysv' Each of the balls 20 :wil'l: becaptive in a retainer l3d' of F a spacer cage 'l'i (whioh inturn willitseli be cap ready deseribed herein .andit 'extends in a diree tivetoarg uideway assemblyby:apair-of the ballS I2 Because each :ofi'the ballszfl -is'tlius captiveit;will -rollialong=:az-straightAline-pathway ontha front surface offa pressure plate; even though =iI; is.- not runningin: a groovebecause it will he 7 guided.rimthatidirectiomby :the;spacerscage hold ing it. Moreover, by properly adjusting the position ofeach tab [3b which is retaining balls 20, each ball 38 can be made toimpinge on a fiat portion of the rear surface of the upright side ratherthan against a shoulder of a pressed-out protrusion thereon so that theball will roll between parallel fiat surfaces, one afforded by the backof the guided side and the other afforded by the surface of a pressureplate which faces it.

At the top and bottom of each of the pressure plates there is a turnedover spacer 2| of such width that the pressure plate can be rigidlyscrewed to an upright side without crushing any of the steel balls I 2or without forcing any of the balls into the material comprising anupright side, a guided side, or a pressure plate; and without bendingany of these component parts. Screws 22 pass through holes at the topand bottom of each of the pressure plates near the spacers and engagethreads in the upright sides so that pressure plates can be drawn intofirm union with the upright sides, i. e. can be drawn against theupright sides until stopped by impingment of the spacers. The screw 22'at top of each pressure plate passes through a hole in a bent over endof tension element 6 before engaging the threads provided in an uprightside. Tension element 6 is thus held in its proper place on the topedges of the upright sides. I

There are two cams 23 each of which consists of substantially circularsheet metal stamping connected to a collar 24, or other suitable elementfor clamping the cam in place on shaft 2, and has a cam raceway 25stamped into its inner surface. Each cam raceway, which, like therectilinear raceways, may have a V-shaped cross section, follows on theinner surface of its cam, a path successive points of which areprogressively nearer to the imaginary center point of the cam collar, orfarther away from it depending upon. the portion of the raceway on whichsuch points are located as well as the direction in which they I aresuccessively considered along that portion. A preferred shape for thepath of a cam raceway is that of the conventional art device used torepresent a heart. Assuming a fixed reference 1 line which is initiallyregistered with a heartshaped cam so as to divide it into two sym--metrical halves, rotation of such a cam for a first 180 from such areference line will either pro--: gressively move the point ofintersection of this motion in a linear manner.

Where maximum manufacturing economy is desired the cam pathway may be acircle with its center offset with respect to the center of the camcollar. A die for pressing such a cam pathway can be inexpensivelyturned out on an ordinary lathe and this will permit considerableeconomy. The linear translation described above Will not be achievedhowever. Rather than this the rate of change will vary in a manner whichcan be predetermined. For certain purposes this will be beneficial andfor others it will not.

As will be described below lug l4 may be formed to contain a ball socketor recess instead of a. transverse raceway. This alternate type of lugis particularly suitable where it is desired to rotate the camcontinuously as a socket will not permit transverse creep of the ballsuch as would occur in a transverse raceway. And obviously forembodiments which do employ a transverse raceway for lug l4 nothing willbe lost if the cam pathway does not follow an endless curve (does notpermit continuous rotation).

It is also possible for the cam to have a spiral pathway so that anumber of complete revolutions of the cam are required for it to drive adriven element in a rectilinear direction for a predetermined distance.This type of construction is particularly suitable where vernier actionis desired.

In assembling the cams to the device of Fig. 1'

" between the lug transverse raceway (or ball socket) and the camraceway each cam is slid along the shaft in the direction of a lug l4until said ball becomes captive between them and is under suflicientpressure to eliminate lost motion crosswise to either of the racewaysholding it. The pressure should not be great enough to bend the cam orbind the moving parts. For embodiline with the cam path away from ortoward the center of the cam collar and rotation of the cam for theremainder of one complete revolution, i. e. for a second 180, willprogressively move said point of intersection conversely, i. e..towardor away from the center of the cam collar. Thus, it is seen that if thiskind of a cam is employed H to drive an element in a rectilinear guideddirection, that element will reciprocate as the cam is continuouslyrotated. Moreover, as can be mathematically demonstrated, if a cam whichone convenient Way of doing so.

ments in which the lug has a socket or recess rather than a transverseguideway it will be preferable to avoid pressure great enough to preventthe ball from slipping around in the socket, i. e. a lug socket will notafford rolling contact and therefore a significant amount of frictioncan be produced by excessive pressure. In such cases accurate formationof the socket surface and the use of a lubricating material will haveobvious advantages.

In Fig. 1 a drive pulley 21 is shown attached to one end of shaft 2. Ithas a recess formed around its edge into which a string (not shown) maybe inserted in a known manner for rotating the pulley under control of aknob and shaft (not 'shown) about which it is customary to wrap enoughturns of the string to provide friction drive from the shaft to thestring which in turn may drive pulley 21. Neither the particular pul-'ley 21, either alone or with particular cooperating drive elements, norany other particular type of drive for shaft 2 is an essential part ofthis invention. This pulley is shown merely to illustrate that shaft 2can have rotary motion imparted to it from an external source and toshow In operation shaft 2 is rotated by a driving force, thus turningcam 23 and causing ball 26 to roll between the cam raceway and the lugraceway. It is readily demonstrable that a ball which is under pressurebetween two plates and rolls without slip-'- any convenient means.

assarzs page between 'two v grooves "therein, =providing present widerretaining surface's' t u m a afforded-by the thickness of thematerialfrom *which the'tabs are-formed. "The presence of these walls willreduce any tendency of the balls to each crane grooves has ballbearing'walIs which aconverge- -at the-same angle "(SO-12,5 to" 'subtendhequal arcs on the -balls spherical surface) will move along each Vgroove wi'th respect to each 5 1 late, a distance e'qual -to onehalf'-of that by -whicli the": two plates :"move with respect to eachother in rolling th ball. i Because'ofthis' the cam .rcan be rotated tomove a 'point' "on its cam race- :point) i'substantially equal'to twicethet'iength: of athestransverse: raceway: in :lug i 4 "before the ball vwill have crept al'ong the transverse racewayfrom "tone of its endstothenther. lfsfor two otherwise i iden'tical embodiments,diiferenti'amounts'c of an- 'ifgiflal rotation of the 'carn arerequired-the transtverse 1 racewayofi .therone afomwhichr the largerwamount ot rotation is required should he longer from that of the other.Where the -widtlr of the punched-out portion of azguidedisidesi does'notrzo "f-provide sufiicient material for a transverse guideway ofadesireddength; transverse guideway of-ithe necessary length' can be madefrom other :materialpfor example, as 'a' separate stamping, -:diecasting, or-theirlike. guideway'thus septa- T'Jrately formed may beattached to the lug by Should it be desired to --"employ a:narrow lugwith airelatively short trans- =versexraceway stamped into it withlesslimita- -:tion of permissible angular-rotation of'the cam ethan thatdescr'ib'edabove, this 'canbe done by :formingthetransverse raceway withits sides az'convergingnat *an' angle substantially less than ithe angleof'convergence of the sidesof the cam rrace'way. "By :doingthis th f'camball will rollin"the tr'ansverse raceway-0n -contact circles hav--:ingrsma1ler radii than those of thecontact cir- .*cuits upon which 'itrides inthe cam'raceway. Therefore, the distance it will creep along thetransverse raceway 'will be less than .the'distance 40 wit will rollalong the cam. raceway. veven this will notpermit continuous rotation.

However,

.;.path. Sincethe ball is captive'in the transverse a -+raceway,-elevatonelement'l=will be driven by lug l-4-nearer to cedar-ther fromshaft 2, thus elevating or 1oweringtop. platform portion ila. Sincetithe svariousaguideway elements are assembled under pressure andsare:virtuetllynoncomprese .visible, @thismovement in th guided directionwill be accompanied by a minimum :of movement in i.anv.other direction.

I-ln YtheQ final-assemblyeofthis entire structure isorews l8nareloosened screws 1'22 are drawn up- :securely and screws Baretightenedagain.

I.I"? ig. ;lir showsooneof -the spaoerrcages. .They

:may besformed of sh'eetsmaterial which is 'i s'ofter. thanlfthematerial.(such-:a-steel) 0f which lthelballs"ZILand-LZ are made.'a-Eachspacer lug m consists oftwo tabsi 3b-sjoined together by 'a U-ilshapedmstrap. Each tab has t-woballretainers 'I3a"punched andpressedth-roughe i-t. Lthesere- Jainer nIe r 1y-.-have ashort retainingwalls r a e ndi erlr ehetea ee ride over the edge of a retainer hole-andclimb out'of' theretainerwhen the elevator element is ---mov'edupanddown. These short walls may be *conveniently formed" by the samestamping operationbywhich the tabs are cut out and the way for .-adistance "(\vith respeet zto'a reference 10* retainer-molespunched-through, If desiri 'bf course,'- -thicker material maybe-used toavoid the "nee'd'for retaining walls other than those afforded'bythesides of the retainer-holes themselves.

'=Fig."-'2shows-an=alternate embodiment in which *a different type ofcam is employed forimparting rectilinear -movement tothe elevatorelement. Theguid'eway-subassemblies of this embodiment neednot bedescribedin detail since, as can be seen from Figs. *2 and they aresubstantially the sameas those ofthe-embodiment of-Fig. 1 which havebeen-fully described above. -'Inth"e embodiment of Fig. 2, however; anoperating" cam 'sur-face is formedon the edge'of each cam" rather thanin its front surface and, accordingly, the lug is formed to"restaga=inst this edge cam sur i face; If a polished -steel 'ball is 'peenedinto' the portion of the-lug which faces said camsur'face it-will'ofieran inexpensive smooth operating and slow W'earing-- surface. From agiven starting -angularpositi'on if the cam isturned in one direction;the camitselfwill impart forceto" the lugtoraise 'elevator element-"'1.Force for-lowering-'e1ement fi -is provided by a" spring. *Spring 28 isconnected betweerrbase'portion "hr-and top portion launder su'fficienttension to 'draw these elements together so that thelug will restagainst thecamdgeflt all times (i.e."will rest there for any rotationalposition of the cam). From the same starting angular --position, if thecam is turne'ol in the opposite directionits cam surface w illtend torecede from thelug. This willpermit spring -'2 8* to draw elevatorelement- 7 downward with the lug in" continuous contact withthe'camsurfa'ce at: a point of contact which moves progres'sively nearer andnearer--to' theshaft'axis. .It isi evident that when the cam is turnedto move -thei'elevator element upwardspring 28 isprozlgressiv'elyloadedand' that in'returning the elevator element toiits'low position spring'28' again becomestun'loadewexc'ept that at" thelowest position'of-element "1 the initial'ten'sion applied ininstallingfithe" spring"-iwillt' remain.-

.fBecause. of the foregoing description of the .guideway portionssoftheldevice of Fig. 1 and of the alternate? form of:raceway.arrangement-using vgrooves-ior wi-shapedcross"section, seeFig.1c, athe embodimentzshowntin Figsn i and ia requires no furtherdescription. In this embodiment there tare two fixedeelements,=one-.of:'which"may be tconsioleredr as" correspondingztto 's anIupright 'side or that devi'ce. ".The'iirnportant fact isthat' there iaretwo lfixed elementsi' connected together with. re. movable guidedelement retained between them, f in 'the manner shown, byi' raceways'stamped in the fixedfelementsiandithe movableelernent and eby c'ballsiicooperating with ith'em 1in a manner already .r fiilly ie-explained.'lThe :purpose of this ".embodimenta isttto guide along a predeterminede-axis 5:1n0ti0n rimparted T ithe movable element rirom a sourceofrmechanical' force'which' may "exert components of force 5 in otherdirections "thanithe 'guidedidirection. F For example, thoughthehandler?Banayrbe:pnshed. generally in a'lftward andrightward-idirecfioninwmg. ii bgfihidtivtion of said line. fixeddistance between the centers of the sockets,

3 lars 30 on shaft 20.

.of collars attached to the cams.

' are formed in anyof a number of ways.

1 ing'force including components downward and inward in the drawing, theaction of the guideway will be to cause movement only along the guidewayaxis with little friction and negligible deviation.

7 Fig. 5 is an alternate embodiment of a device such asthat of Fig. l inwhich each of the cams is adapted to serve a function as a pressureplate. As can be seen each of the guided sides comprises a second lugwhich corresponds to the lug M of Fig. 1e and is located at the bottomedge of the guided side. Since a cam ball is captive above shaftZbetween a cam raceway and a ball recess or socket and a second cam ballis similarly captive below the shaft, this structure provides a way ofexerting substantially balanced pressure against the outside surface ofeach guided side to press it toward the upright side with which itcooperates so as properly to engage the balls l2 captive between theseelements.

Fig. 6 shows a cam raceway suitable for the embodiment of Fig. 5. Thisraceway has a modified heart shape and this figure illustrates the factthat if a line is drawn through the center of the shaft and intersectsthe cam raceway on opposite sides of the shaft, the distance between thetwo points of intersection with the raceway will be constantirrespective of the angular posi- Therefore, though there is a this willnot prevent the desired coaction between a cam and a guided side, i. e.coaction including ,the exertion of pressure by the cam upon the aspiralcam raceway that may be substituted in l. the embodiment of Fig. 5for the heart-shaped carn raceway of Fig. 6.

In the embodiment shown in Fig. 5 an alternate arrangement is shown forinstalling the cams on shaft 2. In this embodiment there are two col-They may either be turned out directly on the shaft or pressed on to it;

shaft in grooves cut into the shaft for the purpose of receiving them.In assembling this de vice the cams are pressed over the shaft ends,

for example in an arbor press, to force them along the shaft until theybear against the collars. This construction facilitates mass productionby unskilled labor and avoids the necessity The positions of the collars30 can be calculated in advance so that when the device is assembled thecams will exert the desired amount of pressure beand balls.

Embodiments have been described herein'as made of sheet metal 'stampingsbecause this economical form of construction is conveniently availableaccording to the nature of this invention. Nevertheless it is obviousthat the various elements herein may comprise guideways which Theupright sides, guided sides and pressure plates may be machine finishedparts if desired or may be die cast. Likewise the annular raceways forcarrying sets of ballsto support shaft 2 maybe 1 machined ratherthanpre'ssed;

- It is also obvious that it is not essential for a device of the kindshown in Fig. 1 that a cam be provided at each end of the device.Instead, for certain applications where extreme rigidity is notrequired, a single cam drive could be employed. For such an embodimentshaft 2 could be made to terminate at a point a short distance inside ofupright side lb and could be supported at that point in a known mannerby a set screw screwed through the upright side and arranged to force asingle polished ball between a first conical recess in the end of theshaft and a sec- .ond conical recess in the end of the set screw, thetwo recesses facing each other. Such a set screw, of course, would alsomake it possible to adjust the pressure on the set of balls 3 in theannular raceway 4 of upright side lc by turning the set screw ratherthan by any manipulation of the tension member.

What I claim is:

1. A device for trans ating rotary movement into rectilinear movementincluding an antifriction guideway comprising two relatively fixedelements connected together with inner surfaces facing each other, eachfixed element having on its outer surface a plurality of straightraceways all parallel to a guided axis of the guldeway, a relativelymovable element surrounding the fixed elements and having raceways onits surfaces also parallel to said axis and registering with theraceways of the fixed elements, and polished balls captive between theregistering raceways, a shaft, a shaft bearing connected to the fixedelements for rotatably supporting the shaft with respect thereto, anelement connected to said shaft and having a surface which issubstantially perpendicular to the axis of the shaft and substantiallyparallel to each of the raceways and to said axis, a cam raceway formedin said surface of said element along a pathway thereon having points atdifferent distances from the center of the shaft, the movable elementcomprising a lug including a ball recess facing said surface of saidelement, and a polished cam ball captive between the cam raceway andsaid recess.

2. A device for translating rotary movement into rectilinear movementincluding an antifriction guideway comprising two relatively fixedelements connected together with inner surfaces facing each other, eachfixed element having on its outer surface a plurality of straightraceways all parallel to a guided axis of the guideway, a relativelymovable element surrounding the fixed elements and having raceways onits surfaces also parallel to said axis and registering with theraceways of the fixed elements, and polished balls captive between theregistering raceways, a shaft, a shaft bearing connected to the fixedelements for rotatably supporting the shaft with respect thereto, anelement connected to said shaft and having a surface which issubstantially perpendicular to the axis of the shaft and substantiallyparallel to each of the raceways and to 'the' shaft, the movable elementcomprising a lug Y including a transverse grooved raceway extendingcrosswise to said axis and parallel to and facing said surface of saidelement, and a polished cam ball captive between the cam raceway and thetransverse raceway.

3. A device for tran lating rotarymovement into guidedrectilinearmovement comprising at 11-13 nleastatwo: anti-frictionqguidewayseachincluding if'hWOJ- relatively fixed relements connected together with:inner surfaces facing and urged towards each lother, a:.:relatively.movable lelement surrrounding the fixed elements with "and having tw:opposite surfaces respectively facing the :outer surfaces of the fixedaelements, s'straight rraceways in at least one of said oppositesurfacessand at least one of said outersurfaces, all of the :racewaysbeinggiparallel tota guided axisof the sguideway and each. individualracewayrregistere sling with*'a=raceway'in a surface facing it, polishedeballs'captivesbetween each outer surface and the -oppositesurfacevfacing it, the balls being under pressure exerted by the connectionwhichurges. :together said inner'surfaces, and. at least some :fiOf the ballsbeing captive between-registering izraceways, 1a baseportion connectedto: atlleas't one; of .thei fixed elements of each guideway so tthatrall of their racewaysare 5 parallel .to :each z-other and perpendicularto the basejportion,;a t-platformrportion connected. to the movableelements of the guideways substantially perpendicurlar torall ofthetracewaysthereof, a shaft, at least eonershaft bearing connected in afixed position" with-respect to-the base and rotatably supporting theshaft; an element'connectedrto the. shaftfland rhaving-ga surface:substantiallytparallel .toiall of "said raceways -wand;,;perpendicular.;to the shaft aa'xisiand' to*.saidrloaseand'rplatformi;portions, assteam" raceway formed "in thesurface of said elegsv mentflalongita paththere'on-havinggpoints unequally' -distant from" the center of'the-1shaft,:-a slug attached to'one of the movaloleelements;v and 1containing 1a 'ballrecess facing said'surfaceacf tsaid: element, andajpolishedcam ball: held cap: -tive:-between 'the cam raceway and saidrecess, awher'eby."rotationalmovements of the shaft apply 'iorce to said:movable element over i said :cam raceway, said-polished camball,and'said lug, and =whereby said -force-will beeifective to move the:imovable'celements and the platform portion atata'ched thereto only .ina-direction along the t guided axis. v

e4..-A-device for translating-asinclaim 3, in-. WhiCh'theci-antf-frictioniguideways: and the base and-iand' the platform:portions together form a mfour-sided boxlike structure-with two opensides, ethe-base and the-platformportions comprising'ia g pa'ir-iofopposed" closed sides andtwo tguideways ccomprising anotl'lerr pair ofopposed closed sides,

"-Jthere are two bearings one formed in a fixed elei mentofone-oftthe'guideways and another formed zwin a fixed elementof theother, the shaft is sup gsportedparallehto 'both the base and platform.

ig'pairof sides comprising the two: guideways; oneof l'.-said-el'ements"having-a surface attached to-:each :s end'of theshaft outside .of the:boxlike structure and there is-vzone of 'saidlalugs attached'ato-lthe.

movableP-elementbf each guideway with its recess facing one of said camraceways and there are two cam ball-siea'ch cafitivebetween a camraceiway andaairecess,whereby saideffective fOIQCGrWfll betr'ansmitted'to the pl'atforrn hy. thenmoveihle elements of bothguideways.

A dev c iifo nans i into guided rectilinear Ino *rotary; movement entcomprising at -deasftwo anti-friction g' ui eways each :"iincludltworelatively'fixed"eleme V geth'er with inn'ensurfacesfa'ci g andurgedftoconnected .tp-

ards each other. a'relativ'ely'imovable. element surrounding thefixed"elements and having j two opposite surfaces respectively facing theouter surfaces-0f the fixed elements straight racemagmas FlWaySiiIlEatdeastnone di said. opposite tsurfaces and eat leastconeitof saidouter-surface s,* all' of=-the raceways 'being: parallel toa1;guided-taxisrofthe "guideway: andzeach individual "raceway register-;.:ing with arac'eway ina surfacefacing it,- polished lba'lls: captive.=between:each' outer surface and the oppositevsurfaceifacing fit; lthe'balls beingxunder rlpressure'sexerted by: the' conn'ectionwhichmrgesfito'getherw" saidrzinner. surfaces andi at least' some of I: the:balls"; being :captive .b'etween registering racewaysea base; portionconnected to .atcleasteone ef:thefixedielementszofeachguidewaysotthatzall 1 of th'einraceways are parallel" to; each; otherand r perpendicular Ito". theubase v:portion, a platform portionconne'cted :to the imovable i: elements fof i 'th' gui'dewayssubstantia11y perpendicular tozxail of the raceways ithereofizaai shaft, attlea'strone "shaft" bearing connected in a fixe'd" position withrespecttozthe .basexand rotatably' supportingzthe 420' shaft, an elementconnected?v to the shaft "and having a surface substantially 1 parallelito ails-6f s'aid ra'ceways and perpendicular tothe shaftlaxis and tosaid :ba e and' platformi portionss a cam -fraoeway formed inthesu'rfa'ce of: said element .25 e1ong=a=path thereon having pointsunequally distaht"f-rom the center -of the' shaftpa lug 'attached to onec'ifthe movable elements: and" containinga transverse' grooved raceway''extending fac ng said surface of said element,=' and a1i-polished ballcaptivdhetweeri themam raceway iand said tran verse raceway.

6. A device for translating asin' claim '5, 'in

whi'ch the antifriction guideways and""'the base and theplatform'portions together form a four- "'sided hox like structure withtwo open sides,' the .--the=platform portions comp'ri'singwa -pz'rirot-opposed closed. "sides 'and two 'guidewayscomprising another pair ofopposed closedsidesgthere lo-are two bearin s one formedin afixed-element of one' o' f'the' guideways and another formed in a "fixedeement of the other, the shaft issupportd '=para1'le1 to both'the baseand platform portions anshas ends which extend beyond the pair of =1sides com rising the two guideways; one" of -said -elen ents havingasurface attached to each end of the shaft outside of theboxlike'structure and "there' is one'of'said lugs atta'ched'to themovable elem'ent of each 'guid'eway" with its transverse o racewayfacing oneof"'said cam raceways and there are: twocamhalls each'captivebetweenta cam' raceway and a transverse raceway, wh'ereibysaid effectiveforcei will-betransmitted to'the :"pl'attorm'by the movable elementsofboth' guideways. Eiportions .andhas ends which extend beyond theJ'Z'JA'clevice'for translatingasin ciaim-3, in which sa'idfixedand'saidimovable elementsare'of sheet materialpdeformablebystamoingi'and'said bearing comprises:anliannularx racewayfstampedfioii-alld z'punjched into one ':'of fthe" fixedstelementssacircumferential b all bearing *groovemut intosfthe 'shaftiat the" pointwh'ereit is su ported bysaid hearingSI -anda row of halls'seated intheiannular ra'cevi ays 'hetw'ee'n' aninn'er surface/there- "of"and'said'ba11 bearing'isurface. v '8.- A- d'evice for translating asinclaim.i3,xin wh ch the anti-friction guidewayatandithe base 'e atfo'rmportions together form a four- 1deboxlikesstructure-iwith:twoiopemsides:the base and the platformportionscoinprising a'p'air of opposed 'closed side's-"and two guidewayscom- 'pr-isinganother pair of opposed -closed sides'fithere aretwobearings" one formed in "a 'fixed ele'-- ment of one of the guidewaysand another formed in a fixed element of theother, the shaft is sup- Tported parallel to both the base and platform portions and has endswhich extend beyond the pair of sides comprising the two guideways, oneof said elementshaving a surface attached to each end of the shaftoutside of the boxlike structure, there is one of said lugs attached tothe movable element of each guidewaywith its recess facing one of saidcam raceways and there are two cam balls each captive between a camraceway and a recess, said fixed and said movable elements are of sheetmaterial deformable by stamping, each of said bearings comprises anannular raceway stamped and punched into a fixed element on a differentone of two opposed closed sides of the boxlike structure, acircumferential ball bearing groove cut into the shaft at the pointwhere it is supported by the bearing, and a row of balls seated betweenan inner surface of said annular raceway and said ball bearing surface,and a tension element connects the 'fixed elements which include theannular raceways and urges them together under pressure sufficient tohold the rows of balls captive between the inner surfaces of the annularraceways and the ball bearing surfaces of the shaft.

9. A device for translating as in claim 3, in which said cam raceway isformed along a pathway on said surface which is of substantially theshape of the conventional art device used to represent a heart.

10. A device for translating as in claim 3, in which the pathway of saidcam raceway on said surface has substantially the shape of a circlewhose center is offset from the axis of the shaft for a predetermineddistance.

11. A device for translating as in claim 3, in which the pathway of saidcam raceway on said surface has substantially the shape of a spiral withits point of origin near to the shaft axis.

12. A device for translating rotary movement surfaces and at least oneof said outer surfaces, a, shaft, cam means connected to said shaft andhaving a surface perpendicular to the axis of the shaft, an off centerraceway formed in the surface of said cam, and means for mechanicallycoupling the movable element and cam whereby the cam controls themovement of said movable element.

13. A device according to claim 12, and in which all of the straightraceways are parallel to the direction of the movement of the guidewayand each individual raceway in alignment with a raceway in the surfacefacing it, and polished balls captive between the aligned raceways.

14. A device according to claim 12, and in which a lugprojects from'themovable element having a ball recess facing the surface of said cammeans, and a polished ball whereby the rotary movement of the cam istranslated into rectilinear movement of the guideway.

l5.-A device for translating rotary motion into rectilinear motion alonga guideway comprising at least two guideways as in claim 12, a base poretion connected to at least one of the fixed elements of each guideway sothat their raceways are all perpendicular to the base portion, aplatform portion connected to the movable elements of -the guidewayssubstantially perpendicular to their raceways, a shaft, at least onebearing conheated to the base portion and rotatably supporting theshaft, a cam attached to said shaft, the cam co'fnprising a sheet ofmaterial substantially parallel to all of the guideways andperpendicular tq' -jsiaid shaft and formed within an eccentric edgehaving different points unequally distant from tlif center of the shaft,the edge being formed with a smooth cam surface, a lug attached to oneofthe movable elements and projecting over the oathsurface, a springunder tension joining the base and platform portions whereby rotarymovements of the shaft in one direction transmit forces to said one ofthe movable elements over the'i cam surface and the lug to drive saidmovable element, and with it said platform portion and said} othermovable portion, in a first direction along the guided axis, androtation of the shaft in thelopposite direction permits forces loadedinto thfe s'pring to act to drive them in the opposite direction.

16. A device for translating rotary motion into rectilinear motion alonga guided axis including a guideway comprising a relatively fixed elementwith an outer surface, a relatively movable element having a firstsurface facing said outer surfac','; a plurality of rectilinear racewaysformed on said surfaces parallel to each other and to the guided axis,raceways on the surface facing each other being positioned to registerwith each other, polished balls between said surfaces in the registeredraceways, a shaft, a bearing connected in a fixed position with respectto the fixed element and' rotatably supporting the shaft with its axiscrosswise to said guided axis, theshaft passing thrpu'gh the surfacessubstantially perpendicular thereto and between the axes of opposedpairs of raceways which register with each other, an eleme 'nt attachedto the shaft and having a surface perpendicular to the shaft axis andparallel to the raceways, a cam raceway formed in said surface along apath having points unequally distant from the center of the shaft, thepathway of the cambeing so formed that any line being drawn through theshaft axis to intersect said pathway onbpposite sides thereof will havetwo: points of intersection with said path which are spaced from oneanother by a fixed distance, two lugs extending from the relativelymovable element toward said surface each lug including a ball recessfacing said surface, and a polished cam ball held'between the recess ineach of said lugs and the cam raceway, the shaft being adapted to urgetoward each other said fixed element and said element having a surfacewith sufficient pressure to keep the cam balls captive between the camraceway and the recesses and the polished balls captive betweenregistered raceways. ARNOLD KO-LKS.

REFERENCES CITED The; following references are of record in the file gofthis patent:

UNITED STATES PATENTS, Number Nam Date g g ,939 Luitweiler et al. July18,1899 resavoo Huffman Dec. 21, 1920 2,028,718 Heine Jan. 21, 19362,050,960

Olivetti Aug. 11, 1936'

